Columba constellation is located in the southern sky. Its name means “the dove” in Latin. The constellation’s original name was Columba Noachi, meaning “Noah’s dove.” It was named after the biblical dove that informed Noah that the Great Flood was receding.
Columba was introduced by the Dutch astronomer Petrus Plancius in the late 16th century and later appeared in German astronomer Johann Bayer’s star atlas Uranometria of 1603. The constellation contains the famous runaway star Mu Columbae, the barred spiral galaxy NGC 1808, and the globular cluster NGC 1851, among other notable objects.
FACTS, LOCATION & MAP
Columba is the 54th constellation in size, occupying an area of 270 square degrees. It lies in the first quadrant of the southern hemisphere (SQ1) and can be seen at latitudes between +45° and -90°.
The constellation contains three formally named stars. The star names approved by the International Astronomical Union (IAU) are Elkurud (Theta Columbae), Phact (Phact), and Wazn (Beta Columbae).
Columba has one star brighter than magnitude 3.00 and no stars located within 10 parsecs (32.6 light years) of Earth. The brightest star in the constellation is Alpha Columbae, also known as Phact. The nearest star is Gliese 218, located at a distance of 48.89 light years from Earth. Columba has one star, designated WASP-63, (spectral class G8) with a transiting planet.
Columba belongs to the Heavenly Waters family of constellations, along with Carina, Delphinus, Equuleus, Eridanus, Piscis Austrinus, Puppis, Pyxis, and Vela. Columba does not contain any Messier objects. There are no meteor showers associated with the constellation.
Columba represents Noah’s dove. Petrus Plancius created the constellation from the stars located behind Argo Navis, the constellation that represented the Argonauts’ ship and was later split into several smaller constellations. Plancius later renamed Argo Navis to “Noah’s Ark” on a celestial globe of 1613.
In the myth, Noah’s dove is sent from the Ark to see if there is any dry land left after the Great Flood. The bird returns holding an olive branch in its beak, signalling that the flood is receding. In some interpretations, Columba represents the dove sent by the Argonauts between the Clashing Rocks to ensure the Argonauts’ safe passage.
MAJOR STARS IN COLUMBA
Phact – α Columbae (Alpha Columbae)
Phact is the brightest star in Columba. It belongs to the spectral class B7IVe. Its name is derived from the Arabic word Al-Fakhita, which means “the dove” or “ring dove.” The star has an apparent magnitude of 2.60 and is approximately 270 light years distant.
Phact is a double star composed of a Be-type subgiant, a suspected Gamma Cassiopeiae type variable with an apparent magnitude varying from 2.62 to 2.66, and a faint companion star with an apparent magnitude of 12.3. The primary star has an expanding gas shell surrounding it.
Wazn – β Columbae (Beta Columbae)
Wazn is a giant star belonging to the spectral class K1IIICN+1. Its name comes from the Arabic word for “the weight.” It is the second brightest star in the constellation, with an apparent magnitude of 3.12. Wazn is approximately 86 light years distant.
δ Columbae (Delta Columbae)
Delta Columbae is a spectroscopic binary star with a yellow giant for a primary component, belonging to the spectral class G7 III. It is approximately 237 light years distant and has an apparent magnitude of 3.853. Its traditional name, Ghusn al Zaitun, is derived from the Arabic phrase al-ghuşn al-zaitūn, which means “olive branch.” The giant star has a close companion with an orbital period of 2.38 years.
γ Columbae (Gamma Columbae)
Gamma Columbae is a blue subgiant (spectral class B2.5 IV) with an apparent magnitude of 4.35. It is located about 854 light years from the solar system.
μ Columbae (Mu Columbae)
Mu Columbae is a runaway star, believed to have been expelled from the Iota Orionis system in the Trapezium Cluster in Orion constellation. It is a fast rotating star that completes a full revolution every 1.5 days, belonging to the spectral class O9.5 V. It is one of the rare O-class stars that can be seen with the naked eye. Mu Columbae is approximately 1,300 light years distant and has an apparent magnitude of 5.15.
ε Columbae – Epsilon Columbae
Epsilon Columbae is a giant star belonging to the spectral class K1 IIIa. It is approximately 531 light years distant and has an apparent magnitude of 3.875.
η Columbae – Eta Culumbae
Eta Columbae is a yellow-orange giant (spectral type K0 III), 531.2 light years from Earth. It has an apparent magnitude of 3.946.
DEEP SKY OBJECTS IN COLUMBA
NGC 1808 is a Seyfert galaxy approximately 40 million light years distant. It has an apparent magnitude of 10.8 and an apparent size of 6′.5 × 3′.9.
NGC 1808 is a barred spiral galaxy that shares a number of similarities with the Milky Way Galaxy. It has an unusual nucleus, shaped like a warped disk, and shows odd flows of hydrogen gas flowing out of the central regions. The galaxy is believed to have a lot of star forming activity occurring in it. A supernova designated SN 1993af, was observed in the galaxy in 1993.
NGC 1851 (Caldwell 73) is a globular cluster in Columba. It has an apparent magnitude of 7.3 and is approximately 39,500 light years distant. The cluster occupies an area 11′ in size.
NGC 1792 is a spiral galaxy with an apparent magnitude of 10.2. It was discovered by the Scottish astronomer James Dunlop on October 4, 1826. The galaxy has an apparent size of 5’.62 x 2’.63.
ESO 306-17 is a type cD3 (E+3) fossil group giant elliptical galaxy located at an approximate distance of 493 million light years from Earth. The galaxy spans about 1 million light years in diameter, which translates to an apparent size of 2.5 arc seconds. It has an apparent magnitude of 13.33.
ESO 306-17 appears alone in a volume of space and is believed to have cannibalized smaller galaxies in its neighbourhood. This is why it is considered to be a fossil group, or the end-result of a galaxy colliding and merging with a regular galaxy group.